If after filing your federal tax return form (Form 1040, Form 1040A, Form 1040EZ, Form 1040EZ-T, Form 1040NR, or Form 1040NR-EZ) you realize you have made an error, you should make sure to file Form 1040X, which is used to address and fix the error. Form 1040X is officially known as the Amended U.S. Individual Income Tax Return and it cannot be filed online. Any refunds will also not be returned through direct deposit; they will be mailed as checks. Furthermore, for refunds, the Form 1040X must be filed within three years after the form with error is filed or within two years after the tax was paid. It must be mailed to the closest Internal Revenue Service Center of the Treasury Department. The link below includes which Service Centers correspond with which states and also includes a blank example of the form. Be sure to allow time for the 8 to 12 week processing time.
The form is not necessary for simple mathematical errors; if you have made a simple miscalculation with your arithmetic, their computer will correct it automatically. But, if you have made any of the following errors, you have to file a 1040X form:
• Misreported the number of dependents
• Misstated your filing status
• Misreported your income (from Forms W-2 or 1099, or an alternate income statement)
• Misreported your withholdings (from Forms W-2 or 1099)
• Misreported your deductions (above-the-line deductions, itemized deductions, or the standard deduction)
• Misreported your exemptions
• Miscalculated your tax credits
First, clearly fill out (correctly) your personal information (name, address, SSN, etc.) and that of your spouse if it is a joint return. Then complete line A accordingly; check "no" if you are living at the same residence as currently listed in the system and check "yes" or leave the box blank if you wish to change the address to that listed on the form. Make sure to also report the year on the form because it does not change annually. Note that the form cannot be used to adjust errors from multiple years; if you have made errors in different years, use separate forms and mail them in separately. It would seem to be a no-brainer, but be sure to properly date and sign the form (including the signature of your spouse if it is a joint return). Failure to make these simple notations will be render the form invalid.
In order to file the 1040X form correctly, you need to determine what you originally reported, what the correct amount is, and why the change is necessary. The form's three-column format should make it easy to correct your mistake. The first column (A) has spaces for the mistakes on the original form. The third column (C) has the adjusted figures. The second column (B) holds the difference between columns A and C. Once you have completed the 1040X form, you need to attach the forms on which the corrections were made (which may also be Form 1040 or W-2) and then simply mail it in.